They just host the site, it is their wiki product called Confluence. The same way Github hosts pages at github.io but has nothing to do with content that people host there.
Oh, I know, I administer Confluence, Jira and Bitbucket. Bar from bitbucket, the other two hosted versions are woefully slow. Don't get me started about the Jira Calendar.
If they're blogging about some tech, maybe they need to dogfood that first.. especially when it's due to performance
As per a previous comment, the contents of the pages linked have as much to do with Atlassian as the contents of a page on github.io have to do with Github.
This is a stanford.edu project wiki page, hosted by Atlassian. Nothing more.
By the same logic, any performance improvement that Github might see from random projects hosted on Github, should be "dogfooded" in the same way.
It's not dogfooding when it's someone else's work.
Atlassian is not blogging about it. Someone else created a Confluence wiki site for RAMCloud using the shared *.atlassian.net domain. Anyone can create a site with a subdomain there.